Model 3

Description of the model


This third model is again a slight variant of the two first, in which we assign a specific \(\alpha\) to each predator, but we also divide it by the degree of the predator (number of preys). In doing so, we can still isolate difference between predator, to check if some predator seems to be different from the whole, but also try to divide between each of ones predators prey. \[\begin{align} F_{ij}^{real} &= \frac{\alpha_{j}}{D_{j}} * B_i * \frac{B_j}{M_j} \end{align}\]

This model was fit with a hierarchy implemented on the alpha parameter. A global alpha was estimated, with 118 respective unique alphas for each predators. In contrast with model 2, the alphas in model 3 are divided by the predator’s degree.

Summary table

Summary table model 3
mean se_mean sd 2.5% 25% 50% 75% 97.5% n_eff Rhat
a_pop -8.048201 0.0021522 0.2830344 -8.604979 -8.240407 -8.050227 -7.861736 -7.478968 17294.18 0.9996497
a_sd 3.674964 0.0016147 0.2018569 3.299842 3.538596 3.666209 3.801799 4.096878 15628.37 0.9997424
sigma 1.744590 0.0002997 0.0329488 1.681984 1.722476 1.743911 1.766623 1.809650 12082.94 0.9998771

Respective predator alphas

One-one plot of simulation against data